Add experimental React Native SwiftPM support

[markmur]

Stacked on #695.

Summary

• adds a parallel opt-in SwiftPM sample project and dev rn spm, dev rn build-spm, and dev rn open --ios-spm commands while keeping CocoaPods as the default
• commits deterministic React Native Codegen output and pnpm patches that supply Swift package manifests for community native dependencies
• replaces Nitro/Quick Crypto with @noble/hashes and react-native-get-random-values for SwiftPM compatibility
• adds experimental SwiftPM sample coverage to the iOS CI workflow

Validation

• dev rn lint
• dev rn test js (13 suites, 238 tests)
• dev rn build
• dev rn snapshot compare
• active-architecture SwiftPM iOS simulator build